Xolair Drug Interactions

Since IgE may be involved in the immunological response to some helminth infections, Xolair may indirectly reduce the efficacy of medicinal products for the treatment of helminthic or other parasitic infections (see Precautions).
Cytochrome P450 enzymes, efflux pumps and protein-binding mechanisms are not involved in the clearance of omalizumab; thus, there is little potential for drug-drug interactions. Medicinal product or vaccine interaction studies have not been performed with Xolair. There is no pharmacological reason to expect that commonly prescribed medicinal products used in the treatment of asthma, CRSwNP or CSU will interact with omalizumab.
Allergic asthma: In clinical studies Xolair was commonly used in conjunction with inhaled and oral corticosteroids, inhaled short-acting and long-acting beta agonists, leukotriene modifiers, theophyllines and oral antihistamines. There was no indication that the safety of Xolair was altered with these other commonly used anti-asthma medicinal products. Limited data are available on the use of Xolair in combination with specific immunotherapy (hypo-sensitisation therapy). In a clinical trial where Xolair was co-administered with immunotherapy, the safety and efficacy of Xolair in combination with specific immunotherapy were found to be no different to that of Xolair alone.
Chronic rhinosinusitis with nasal polyps (CRSwNP): In clinical studies Xolair was used in conjunction with intranasal mometasone spray as per protocol. Other commonly used concomitant medicinal products included other intranasal corticosteroids, bronchodilators antihistamines, leukotriene receptor antagonists, adrenergics/sympathomimetics and local nasal anesthetics. There was no indication that the safety of Xolair was altered by the concomitant use of these other commonly used medicinal products.
Chronic spontaneous urticaria (CSU): In clinical studies in CSU, Xolair was used in conjunction with antihistamines (anti-H1, anti-H2) and leukotriene receptor antagonists (LTRAs). There was no evidence that the safety of omalizumab was altered when used with these medicinal products relative to its known safety profile in allergic asthma. In addition, a population pharmacokinetic analysis showed no relevant effect of H2 antihistamines and LTRAs on omalizumab pharmacokinetics (see Pharmacology: Pharmacokinetics under Actions).
Paediatric population: Clinical studies in CSU included some patients aged 12 to 17 years taking Xolair in conjunction with antihistamines (anti-H1, anti-H2) and LTRAs. No studies have been performed in children under 12 years.